9. Electric Connection
The electric connection should be made by a specialist.
To avoid short circuits and resulting damage to the device, the negative pole (earth) of the vehicle battery
must be disconnected during connection.
Only connect the negative pole of the battery when you have completely connected the system and
checked the connections.
You should only use a voltmeter or a diode test lamp for checking the voltage of the on-board cables, as
normal test lamps consume excessive currents and can thus damage the electronics system of the car.
When laying the cables, make sure that they are not squeezed or scoured on sharp edges. Use rubber
grommets for the feed-though points.
The line towards the speakers must be a bifilar cable. Insulate any open connection points. Make sure that
the cables are not damaged by sharp edges.
Only use speakers with sufficient load capacity (see "Technical Data").
Observe that all speakers have the correct polarity - that is, that plus and minus marks match.
The connecting cables of the loudspeakers are usually coded: Some speaker manufacturers indicate the
(+) wire by means of an additional colour stripe, others use a corrugated cable for the (+) terminal and a
smooth one for the (-) terminal.
The system was designed for the operation at speaker impedances of at least 4 Ohm. Never connect
speakers with a lower impedance.
In most vehicles, the cables for the electric connection and the connection of the speakers have been laid
directly to the slot.
If this is not the case, please make sure that any cables placed later are secured by the respective on-board
fuses (see vehicle operation manual).
a) Connecting the Aerial
• Connect the aerial plug of your vehicle with the aerial socket at the back of the radio.
• If your vehicle has a different aerial plug, please use a suitable adapter, available in specialist shops.
39